Method of producing rectifying units



July l, 1930.a vc. E oGDl-:N 1,769,852

METHOD OF PRODUGING' RECTIFYING UNITS Filed June 27, 1927 C/L ORI/VE i `Patented July l, 1930 I ing units is particularly adaptable to the new UNITED STATESv PATENT OFFICE CLARENCE E. OGDEN, OF CINCINNATI, OHIO, ASSIGNOR TO THE KODEL RADIO COB- POBATION, A CORPORATION OF OHIO METHOD 0F YRODUCING RECTIIE'YING UNITS .Application filed June 27,

The present invention relates to the method of producing rectifying units particularly of the copper oxide type.

In rectlfying units of'the copper oxide type, the eliectiveness of the units is provagent during the heat treatment of the metallic plate for the formation of the oxide, thejormation ofsuch oxide is facilitated and the la er orm materially increased. I have also diiscovered that the length of time involved in cooling the ,units after the same` have been raised to the required temperature is important to the relation of the internal resistance of the units; that is, the more -rapidly the unit is cooled after being raised to the required temperature the lower the internal resistance of the unit.

The object of the present invention is, therefore, to derive in the production of rectiying units the benefits from such discoveries.

In the drawings:-

Figure 1 is al view illustrating the method of carrying into eect the present invention.

Figure 2 is a sectional view of a rectifying unit constructed in accordance herewith.

The present method of producing rectifytype' of copper oxide units which have lately been developed in which the surface of the layer of copper oxide is again reduced to metallic copper after oxidation by quenching the unit in a bath, for instance', of alcohol and water. In the;l production of such units it is important that the unit -be quenched in the bath when itis ata temperature not higher than 1400 degrees Fahrenheit. As the heat tSreatment of the units requires that they be 'raised to approximately 1900 degrees Fahrenheit, there must be an intervai of partial cooling before' the units are quenched and in order to minimize the internal resistance of the units the period of cooling must .be reduced as much as practicable.

1927. Serial No. 201,662.

as a catalytic agent in the formation of the Y oxide layer or layers on the metallic plates and enhances the production of such oxide so that the layer formed is comparatively thicker and therefore in the completed unit more effective than where such agent is not employed. After the copper or other metallic plates have been'raised to the requisite temperature in the furnace, that is, to approximately 1900 degrees Fahrenheit, for the formation of the oxide, they are then removed in the presence of an electric fan or other mechanical cooling means 3, causing rapid radiation and dissipation of the heat of such units until the temperature is reduced to approximately 1400 degrees Fahrenheit, at which temperature they are quenched in a suitable bath Solution in the tank 4. As it i is not always possible to control the cooling process before immersion in the bath within the desired limits, I have found that it is ordinarily most practicable to cool the units somewhat lower than the immersion temperature of 1400 degrees Fahrenheit then reheat by placing them in a second furnace 5 before quenching them in the bath, said furnace being maintained at the desired temperature of 1400 degrees Fahrenheit.

Having thus fully described my invention, what I claim as new and desire to secure by Letters Patent is:

1. The method of producing a rectifying unit, comprising raising a copper plate to a temperature of approximately 1900 degrees F. in the presence of oxygen and chlorine, then rapidly partially cooling said plate, then quenching same in a bath adapted partially to reduce the oxide to metallic copper. 2. The method of producing a rectiying unit, comprising raising a copper plate to a temperature of approximately 1900 degrees F. in the presence of oxygen, then rapidly partially cooling said plate, then raising the plate to a quenching temperature, then quenching said plate in a bath adapted partislly to reduce the oxide to metallic co per.

3. The method of producing a. recti ing unit, comprising raising a. copper plate to a. temperature of approximately 1900 degrees 5 F. 1n` the resence of o gen and chlorine, then rupi y artially coo 'ng said plate, then raising the p ate to a quenchmg temperature, then' uenchin said plate in a. bath adapted partis, 1y to re uce the oxide to metallic cop- P04. In the method of producing a rectifying unit, the step of heating a copper plate to a temperature of approximately 1900 degrees F. m the presence of oxygen and chlo- 15 Ille.

* CLARENCE E. OGDEN. 

